About 100 researchers, health workers and activists who died on the Malaysia Air flight were en route to a global AIDS conference in Australia.

The world was stopped in its tracks yesterday upon hearing the news of the downed Malaysia Air flight en route from Amsterdam to Kuala Lumpur. It may be some time before we know what really happened to that flight, but what we do know for now is that none of the 297 passengers and crew survived. And while the world mourns the loss of every single one of those lives, one group has been hit particularly hard by this crash. About 100 top-level AIDS researchers and activists were onboard the flight on their way to a global AIDS conference in Australia.

According to the Sydney Morning Herald, the researchers, health workers, and activists were on their way to the International AIDS Conference in Melbourne. Among the victims was Dutch national Joep Lange, a top AIDS researcher and former International AIDS Society president; and Glenn Thomas of the United Kingdom, a spokesperson for the World Health Organization and a former BBC journalist.

The International AIDS Society responded to the news yesterday with this statement: “At this incredibly sad and sensitive time, the IAS stands with our international family and sends condolences to the loved ones of those who have been lost to this tragedy.”

And while the AIDS research community mourns the loss of their colleagues, they also fear the loss of expertise that went down with that flight. The researchers aboard were some of the highest-level AIDS researchers in the field, and many fear that AIDS research could be stalled for some time by their loss.